Artificial denture



Oct. 11, 1966 w. s. STASIW 3,277,575

ARTIFICIAL DENTURE Filed March 26,. 1964 fy i I INVENTOR.

ZI/a/fer 5 Sfasz'zu ATTORNE q United States Patent 3,277,575 ARTIFICIAL DENTURE Walter S. Stasiw, 10315 Jos. Campau, Detroit, Mich. Filed Mar. 26, 1964, Ser. No. 354,912 11 Claims. (Cl. 322) This invention relates to artificial dentures and more particularly to an improved artificial tooth and prosthetic appliance construction which can be used to advantage in full dentures or in partial dentures or bridges.

The function of conventional artificial teeth in dentures tends to be ineflicient due to the instability of the dentures within the mouth. That is, the dentures, and especially the lower, tend to become loose. This lack of retention makes it difiicult for the chewing members, i.e., the teeth, to masticate food effectively and efiiciently while at the same time providing comfort to the wearer. The resultant movement, slipping and lifting of the denture bases often results in soreness to the underlying tissues of the mouth, more rapid resorption of the underlying bone due to trauma exerted upon the supporting structures, difiiculty of the chewing or mastication of food, and often embarrassment to the wearer. The chief cause of these problems is primarily related to the present day design and function of the posterior teeth, i.e. the bicuspids and molars. The upper and lower cusps on the occlusal surfases of conventional teeth interlock when the jaws close into occlusion. Since these conventional prosthetic teeth are fixedly secured to the denture base, this prevents smooth and continuous forward and backward as well as lateral movement without tendency to displace the denture or dentures. Hence, the dentures are caused to slide or tilt off of their foundation when forces are exerted by the mandible in a lateral or anterior-posterior direction.

It is an object of the present invention to provide an improved artificial tooth and denture construction which affords greatly increased stability and retention of the dentures within the mouth, thereby improving comfort and masticating efiiciency.

Another and related object of the invention is the provision of an improved artificial tooth and denture which compensate for premature tooth contact in occlusion and which alleviate the problems arising from upper and lower occluding teeth being out of centric relationship due to dimensional changes which occur in the various materials employed in denture construction, changes which occur in vertical dimension or to other factors which normally tend to cause an out of centric relationship.

Briefly, the above objects are accomplished in accordance with the invention by an artificial tooth which is spherical and which is received in a mating spherical shaped socket in the denture base to thereby be rotatable in the socket in all directions. Further in accordance with the invention, in the construction of a denture plate only the posterior teeth are of the aforesaid construction, the anterior teeth, those from about the first upper bicuspid forward, are conventional duplicating the appearance of natural anterior teeth to preserve aesthetic appearance. Where both the upper and lower plates are constructed in accordance with the invention, the opposed spherical teeth in the posterior quadrants are arranged 'so as to be in substantial centric relationship, the spherical teeth in one plate preferably being larger and fewer in number than those in the opposed plate. For optimum ease and economy of manufacture, the spherical shaped sockets for the teeth can be provided by way of a metal or plastic cage which can be inserted or embedded in the denture base material. Further, for hygienic purposes in particular, the cage or other socket 3,277,575 Patented Oct. 1 l 1 966 ice member is constructed, in accordance with the preferred embodiment of the invention, in such manner as to allow easy disassembly of the spherical teeth from the sockets. Hence, the sockets and the teeth can be easily and thoroughly cleaned.

Artificial teeth and dentures constructed in accordance with the invention enable the wearer to have free and easy lateral and anterior-posterior movement of the mandible without interlocking of the antagonistic teeth. This freedom of cusp lockage prevents sliding of the dentures upon the ridges, prevents tilting or dislodging of the denture bases, and greatly reduces or dissipates occlusal forces so that undesirable trauma is reduced to a minimum. The freely rotating teeth render the dentures more easily slidable relative to each other than to the ridges on which they rest. Hence, there is afforded maximum ridge contact of the upper and lower denture bases with minimum cuspal interference with any mandibular movement. Since the paths of the mandibular movements are numerous and vary with each individual due to such controlling factors as the anatomy of the joint, chewing habits, etc. it is extremely difiicult if not impossible with conventional artificial dentures to provide a construction and fit which conforms to the individual patient. With the present invention cuspal interference with mandibular movement is eliminated or at least greatly alleviated irrespective of the precise habits and joint structure of the patient, thereby substantially reducing deleterious stresses and strains on the gum tissues and underlying bony ridges.

The above and other objects, features and advantages of the invention will appear more clearly from the following detailed description of preferred embodiments thereof made with reference to the appended drawings in which:

FIGURE 1 is an occlusal surface view of upper and lower artificial denture plates embodying the present invention;

FIGURE 2 is a side view of the denture plates shown in FIGURE 1 in occlusal relationship, certain of the posterior construction of the denture plates being shown in broken outline;

FIGURE 3 is a fragmentary view taken on the line 3-3 of FIGURE 2 and showing one quadrant of the lower denture plate of FIGURE 1 with the tooth occlusal surfaces of the upper plate being shown in broken outline;

FIGURE 4 is a fragmentary sectional view, in enlarged scale, taken on the line 4-4 of FIGURE 1, and

FIGURE 5 is a fragmentary sectional view, in enlarged scale, taken on the line 5-5 of FIGURE 3.

Referring now to FIGURE 1, the upper denture plate 6 comprises a base member 8 formed of conventional material used for such purpose and shaped at its upper surfaces 10 in the usual manner to conform snugly to the gum pattern of the patient. The teeth 12 which are anterior to the second bicuspid, that is, from the first bicuspid forward, are of conventional shape and structure closely duplicating the appearance of natural teeth for aesthetic purposes. In accordance with the present invention, the posterior teeth 14 in each quadrant of the top plate are spherical and are received in mating spherical shaped sockets 16 in the plate base member, each tooth being in slidable engagement with its socket whereby it can freely rotate in all directions within its socket. Referring now to FIGURES 2 and 4, the latter in particular, in the preferred embodiment shown, the sockets 16 are provided by way of an elongate cage 18 which is embedded in the material of the base member 8. The cage includes a body 20 of suitable material, such as acrylic plastic, shaped with three substantially hemispherical recesses 22, and a thin metal plate 24 having three round openings aligned with the hemispherical recesses in the body 20. The plastic body 20 is bonded or otherwise secured permanently to the material of the base member 8 and the plate 24 is removably secured to the body 20 by means of a pair of integral metal pins 26 which are matingly received by openings 28 formed in the body 20 adjacent the hemispherical recesses. Each pin 26 has an annular groove adjacent the end thereof which forms a snap or resilient connection with the mating flange formed on the inherently resilient plastic material of the body member. It will be noted that the walls of each of the round openings in the metal plate 24 are contoured to form a continuation of the spherical surface of the recess with which the opening is in alignment, and engages the spherical tooth slightly below the central plane thereof. Hence, with the plate 24 secured to the plastic body 20, the teeth are retained within their respective spherical sockets. However, upon removal of the plate from the body 20 by snappingly disengaging the pins 26 from their respective openings 28, the spherical teeth can be lifted out to allow cleaning of the teeth and sockets. Also, this disassembly feature enables simple replacement of the teeth if they become worn or broken. If desired, a small slot or opening 30 (see FIG- URE 1) can be formed at the edge of the metal plate 24 to enable it to be pried loose and therefore easily disassembled from the denture base. It will be understood, of course, that any of various cage structures can be used and that other means for allowing disassembly for cleaning purposes can be used in place of that shown in FIGURE 4. For example, small screws to secure the cage parts together can be used, or, if desired, the entire cage can be made of a plastic or other material with some inherent resiliency and the spherical shaped recesses therein formed with a section of only slightly more than 180 whereby the spherical teeth may be resiliently snapped in and out of the recesses, as will be further described hereinafter. To inhibit food from lodging between adjacent spherical teeth, it is desirable that the row of teeth within each cage be as close together as possible while still allowing each to freely rotate within its socket.

Referring again now to FIGURES 1 and 2, the bottom denture plate 34 has a base member 36 of conventional shape with the teeth 38 anterior to the second bicuspid also being of conventional shape for aesthetic purposes. In accordance with the present invention, the posterior teeth 40 are spherical and are received in spherical shaped sockets 42 for free rotation therein in all directions. This is shown in FIGURE 2. In the particular embodiment shown, a total of 12 relatively small spherical teeth arranged in two rows of 6 each are used in each quadrant of the lower plate, and a single row of three relatively large spherical teeth are used in each quadrant of the upper plate. As best seen in FIGURES 2 and 3, the teeth are arranged such that the three upper teeth are in centric relationship to the lower teeth, each upper tooth meshing centrically with four of the smaller lower teeth. It will be understood, however, that various other arrangements may be used, all in accordance with the invention, the precise arrangement being determined on the basis of what is judged best by the dentist for the particular patient involved. For example, different numbers and sizes of upper and lower spherical teeth may be desirable and it may be desirable to use different numbers of rows.

The structure for removably retaining the spherical lower teeth in their sockets is shown in FIGURE 5. Such structure comprises a cage consisting of an elongate thin metal plate 44 formed with two rows of spherical shaped depressions each for receiving one of the spherical teeth. The plate 44 is embedded in and bonded or otherwise secured to the lower plate base member 36 and each spherical depression has a small opening at the bottom thereof which is aligned with a bore 48 through the plate base member to the underside thereof. Each of the spherical shaped recesses is slightly greater than 180 in section as shown, such that it encircles slightly more than one-half of its mating spherical tooth. Hence, the tooth is retained within its socket. However, the inherent resiliency of the metal plate 44 enables each tooth 40 to be snapped out of its socket by inserting a small pin or the like through the opening 48 and against the tooth 40 to apply sufiicient pressure to snap it out of the socket. If desired, the bore 48 and its aligned opening in the spherical depression can be eliminated and replaced, for example, by forming a small diagonally extending narrow slot at the opening of the spherical depression as indicated at 50, thereby allowing a pin to be inserted into such slot to bias the tooth out of its socket.

The spherical teeth may be made of any of a variety of materials, for example, metal, plastics such as acrylic, porcelain or any of the other materials commonly used for the manufacture of denture teeth.

The freely rotatable posterior teeth provide greatly increased stability to the denture bases in the mouth, even though they be or should become slightly out of centric relationship, in lateral or protrusive excursions or when undesirable forces are applied which would otherwise tend to dislodge the plates. Hence, damage or soreness to underlying structures of the month are alleviated, the patients comfort is improved, and there is increased masticating efiiciency. Undesirable cuspal interferences in premature contacts and interdigitation are substantially alleviated.

While in the preferred embodiment as shown all of the spherical teeth, both top and bottom, are rotatable in their sockets, in some cases it may be desirable to use the rotatable spherical teeth as described only in the upper or the lower denture using for the opposed teeth in the other denture teeth which are spherical or generally rounded out which are in fixed or nonrotatable position in the denture base. Hence, it will be understood that while the invention has been described specifically with reference to certain preferred embodiments thereof, various changes and modifications may be made, all within the full and intended scope of the claims which follow.

I claim:

1. In an artificial denture, a member having a generally spherical shaped socket, and a generally spherical tooth in slidable mating engagement with said socket.

2. An artificial denture comprising a gum engaging member having a spherical shaped socket, and a spherical tooth retained in mating engagement with said socket and rotatable therein in all directions.

3. An artificial denture as defined in claim 2 wherein said tooth is removably retained in said socket whereby said tooth can be disassembled from said member.

4. An artificial denture as defined in claim 2 wherein said socket has resilient means to removably retain said tooth therein.

5. In an artificial denture, a gum engaging base member having a plurality of posterior spherical shaped sockets each receiving a spherical tooth rotatable therein in all directions.

6. An artificial denture comprising a gum engaging body, a cage having a plurality of closely adjacent spherical shaped sockets therein secured within such gum engaging body and a spherical tooth in each of said sockets and rotatable therein in all directions.

7. An artificial denture as defined in claim 6 wherein said cage includes means for disassembling said teeth from said socket.

8. An artificial denture as defined in claim 6 wherein said cage comprises a body portion and a plate removably secured to said body portion, each of the spherical shaped sockets being formed by spherical shaped recess in said body portion and a round opening in said plate aligned with the recess.

9. An artificial denture plate having anterior teeth which are substantial facsimiles of natural teeth and having posterior teeth which are spherical and are received in spherical sockets for rotation therein in all directions.

10. A pair of artificial denture plates, each of said plates having posterior teeth which are of generally spherical shape, at least some of said .teeth being matingly received in spherical shaped sockets for rotation therein, said teeth being so arranged that those in one plate are in substantially centric relationship to the teeth in the other of said plates.

11. A pair of false denture plates as defined in claim 10 wherein the spherical-shaped teeth in one of said plates are larger in size and fewer in number than the sphericalshaped teeth in the other of said plates.

References Cited by the Examiner UNITED STATES PATENTS 2,941,295 6/1960 Jermyn 322 RICHARD A. GAUDET, Primary Examiner. R. E. MORGAN, Assistant Examiner. 

1. IN AN ARTIFICIAL DENTURE, A MEMBER HAVING A GENERALLY SPHERICAL SHAPED SOCKET, AND A GENERALLY SPHERICAL TOOTH IN SLIDABLE MATING ENGAGEMENT WITH SAID SOCKET. 